点击按钮时如何自动递增和递减计数

Question

我有两个按钮叫＆＃34; +＆＃34;和＆＃34; - ＆＃34;。

如果我点击＆＃34; +＆＃34;按钮我必须将计数值增加到最大值＆＃34; 7＆＃34;如果我点击＆＃34; - ＆＃34;按钮我必须减少计数值，如果值达到＆＃34; 1＆＃34;价值不能改变，因为最小的我有＆＃34; 1＆＃34;作为默认。

这是我的示例代码：

@IBAction func seat_btns(sender: AnyObject) {

    if sender.tag == 10 {

        let i : Int!

        let s = self.seatNumberLabel.text
        if let x = Int(s!) {
            i = x + 1
            self.seatNumberLabel.text = i.description

        }

    }
    else if sender.tag == 20 {
        let s = self.seatNumberLabel.text
        let i : Int!

        if let x = Int(s!) {
            i = x - 1
            self.seatNumberLabel.text = i.description

    }

    }
}

Answer 1

简单的if检查可以为您提供帮助

@IBAction func seat_btns(sender: AnyObject) {

    if sender.tag == 10 {

        let i : Int!

        let s = self.seatNumberLabel.text
        if let x = Int(s!) {
            if (x < 7) {
                i = x + 1
                self.seatNumberLabel.text = i.description
            }
        }

    }
    else if sender.tag == 20 {
        let s = self.seatNumberLabel.text
        let i : Int!

        if let x = Int(s!) {
            if (x > 1) {
                i = x - 1
                self.seatNumberLabel.text = i.description
            }
        }

    }
}

Answer 2

for max 7

i = max(1, min(x + 1, 7))

for min 1

 i = max(1, min(x - 1, 7))

编辑：

if sender.tag == 10 {

        let i : Int!

        let s = self.seatNumberLabel.text
        if let x = Int(s!) {
                i = max(1, min(x + 1, 7)
                self.seatNumberLabel.text = i.description
        }

    }
    else if sender.tag == 20 {
        let s = self.seatNumberLabel.text
        let i : Int!

        if let x = Int(s!) {
                i = max(1, min(x - 1, 7)
                self.seatNumberLabel.text = i.description
        }
}